1. Field of the Invention
This invention relates to an apparatus for deweaving a fabric tape into individual strands so they may be wound on separate packages for subsequent use. Deweaving the tape is an essential process when space dyeing of textile yarns is carried out via the weave-de-weave process, since the tapes themselves cannot be used as a unit for further processing.
2. Description of the Prior Art
U.S. Pat. No. 3,605,225 describes in detail a weaving process which is commonly referred to as "weave-de-weave". Weft is inserted by a needle on a narrow width needle loom and knitted in a chain stitch along one side of a tape fabric including a plurality of warp threads in order that the weft can subsequently be removed after treatment of the fabric, e.g., by coloring, and the fabric unravelled to provide a yarn with intermittent coloring or splotches which is then used as pile yarn in carpets.
As the weft is removed, the individual warp yarns from the tape are separated out and wound on single one-end packages.
Typically, the yarn used for the weft filling is either nylon or polyester of a size substantially smaller than the warp yarn through which it is woven. For purposes of economy, the weft yarn must be reclaimed for repetitive use and with each re-use, the cost of the weft per pound of carpet yarn produced is decreased. However, there are serious drawbacks in re-using the weft yarn. Owing to its fine denier and to repeated subjection to both heat (during dyeing) and stress (during weaving and deweaving), the efficiency of the latter operations decreases with each re-use.
One problem associated with weft removal in the "weave-de-weave" process, therefore, is breakage of the weft thread or the presence of a knot or tangle in the weft thread as it is deweaved. This problem is compounded by the method of weft collection in which the use of a conventional ring traveler take-up is involved, which inserts variable twist in the weft end, consequently increasing the incidence of breakage and snarls in re-use of the weft. If the weft breaks or tangles, the de-weaving process must stop. Broken ends must be rethreaded and repaired, and yarn tensions readjusted, all of which gives rise to considerable process inefficiency and additionally requires operator attention.
Knots and tangles, as well as breakage, of the warp threads in the process is also a problem because of the simultaneous winding of a large number of parallel yarns onto separate packages. If a knot, tangle, or breakage of a warp thread occurs, the individual warp threads cannot be properly separated, and the entire process must stop.
Accordingly, because of the possibility of breakage and knots or tangles of the warp and weft yarns, such conditions must be quickly detected in the deweaving process and the deweaving apparatus stopped, so that appropriate corrective action can be taken before a broken yarn, by becoming entangled with adjacent yarns, creates numerous additional yarn breaks and tangles.